Instead of declaring all resources within a single ARM template, the entire solution has been decomposed into multiple smaller ARM templates, each responsible for a single resource, or a group of related resources.

The single resource templates created after decomposition are these:

• appserviceplan-1.0.0.0 
• webappsimple-1.0.0.0

The appserviceplan-1.0.0.0 ARM template is responsible for creating an App Services plan. This plan is needed for creating a web app.

The webappsimple-1.0.0.0 ARM template is responsible for creating an App Service web app. It uses the already created App Service plan.

Related resources can be grouped together that share the same life cycle in terms of provisioning and deprovisioning. The SharedServicesSQL-1.0.0.0 ARM template consists of multiple resources all related to Azure SQL. These resources include SQL Server, SQL Database, and SQL firewalls.

The SharedServicesSQL-1.0.0.0 is also a shared template that can be used not only within the current scenario but also by other projects. Any project that needs to provision Azure SQL can use this template as is, by providing configuration information. The SharedServicesSQL-1.0.0.0 ARM template can also be thought of as a technical capability template that provisions a capability completely. An example of such a capability would be a virtual machine template comprising of multiple related resources such as a public IP address, a network interface card, storage accounts, and so on.

Let's go through these subtemplates and understand their code.